The use and functioning of emergency lights for providing illumination upon loss of AC power is well known. These emergency lights are now found in interior areas which lack outside illumination and which require artificial illumination to provide for the safety of people in such areas. Many statutes and ordinances exist which require such emergency illumination in public places, such as theaters, stairwells, and elevators.
There are, however, many specialized applications in which emergency lighting would be desirable, but for which suitable emergency lighting fixtures are not available. Such applications include off-shore drilling rigs, and certain manufacturing environments where potentially explosive atmospheres may be present. Since normally emergency lights include electronic circuitry which may spark and bulbs which can break to expose a hot filament to the atmosphere, such an emergency light would not be suitable for use in explosive atmospheres. Accordingly, an explosion-proof emergency light has potentially widespread application.